Vehicle safety devices can generally be classified as passive, active safety or post crash safety devices. Active safety devices are aimed at collision avoidance, and include safety devices and systems such as anti-lock braking, electronic stability control, traction control and head-up displays.
Passive safety devices are aimed at reducing the effects of a vehicle collision, and include crumple zones, air bags, safety belt tensioners, collapsible steering columns and the like. These devices help protect the occupants of a vehicle during an accident. Post accident safety devices are aimed at injury mitigation, and include devices that isolate a vehicle's power supply, activate hazard lights, notify emergency services of the incident and the like.
In a significant number of severe motor vehicle accidents occupants become trapped within a damaged vehicle. Often, the occupants cannot be extricated by emergency personnel without the assistance of specialised vehicle extrication equipment. Vehicle extrication equipment, such as hydraulic rams, cutters and spreaders (such as the so-called Jaws of Life), are generally very expensive and are typically carried only by fire engines and specialised accident units which are not always a primary response to accidents. In addition, even where vehicle occupants are not trapped within a damaged vehicle, extrication techniques may be used in order to give paramedics and emergency personnel better access to the occupants to treat the occupants and remove them without obstruction which could further exacerbate injury. In many motor vehicle accidents, the emergency personnel that are first to arrive on the accident scene are generally unable to assist the occupants until the vehicle extrication equipment arrives, and the resultant delays can result in further occupant injury or even death. Most vehicle safety specifications measure only the extent of active and passive safety devices, which are effective only until immediately after the accident.
There have been recent attempts by manufacturers of motor vehicles to provide safety systems that extend beyond the scope of active and passive safety devices. For example, systems that unlock doors, turn on interior lighting, shut off fuel supply, disconnect the battery terminal from the alternator or automatically notify a response centre in the event of an accident are known. These systems, however, do not provide sufficient means for enabling the occupants of badly damaged vehicles to be extricated or accessed without the use of specialised vehicle extrication equipment.
Significant damage is generally caused to a vehicle during occupant extrication. Very often components of the vehicle which were not damaged during the accident become damaged beyond repair as a result of the extrication. Such damage often results in a vehicle being completely written off whereas it may otherwise still have been viable were it not necessary to use extrication equipment.
In recent years motor vehicle manufacturers have started using stronger materials to enhance the safety performance of vehicles such as UHSS/Boron (Ultra High Strength Steel) and HSLA (High Strength Light Alloy) in the production of vehicles. These materials require specially adapted cutting equipment with strengthened cutting edges and increased pressure outputs which are not always readily available to emergency personnel.
In this specification the term “pillar” refers to a structural element of a vehicle that extends between the roof of the vehicle and lower parts of the vehicle body. In an automobile, the gaps between pillars are typically used for doors and windows. The “A-pillar” refers to the pillar closest to the front end of a vehicle which typically supports the windshield, the “B-pillar” is the second pillar from the front end on which vehicle doors are typically hinged, and the “C-pillar” is the third pillar from the front end, which may be the rearmost pillar supporting the rear windshield or may be an intermediate pillar. Further pillars, such as D-pillars or E-pillars may be provided depending on the type of vehicle. The term “body” in relation to a vehicle includes the roof of the vehicle. In addition, the term “vehicle” is intended to include within its scope, motor vehicles and aircraft, particularly light aircraft both fixed and rotary winged.